Digestive system problem. Please help!

Had chronic constipation. And 2 months ago I had got blood in my stool for two days. Then I took " Vaidhrishi's Arshkalp Capsules" next day there was no blood, even till date I have notgot any blood in stool. I started taking Zandu Nityam Tabs (laxative) daily for constipation. I am having regular Bowel movements but thrice a day. And there is Mucus in my stool. Sometimes irritation in the anus after movement. Sometimes  itching at the rectum. There's too much gas. It comes out with frequent belchings and with stinky farts. I fart too often sometimes farting doesn't stop at all. Sometimes I see undigested food in stool. Today I saw a very small tiny white color lice or bug like thing was moving in stool. What's happening I don't know please help. Is it piles/hemorrhoids or just a bacterial infection. Please help